Digital cameras are known, each of which electrically converts object images formed by an image-taking lens into image signals using a solid image-pickup device such as a CCD sensor, records A/D-converted image signals to recording medium, and displays images on a built-in liquid crystal monitor.
Especially, in a single-lens reflex digital camera including an interchangeable lens, it is required to have a good operationality, high-speed continuous shooting performance, high quality image taking ability and image taking ability for wide luminance range, similar to silver-halide film cameras. For these requirements, the digital camera comprises an image-pickup device having many pixels and a high sensitivity, and furthermore a larger-scale electronic circuit including many electronic devices such as an image-taking circuit, image-processing circuit and image-displaying circuit than that of the silver-halide film camera.
Therefore, the digital camera consumes a large amount of electric power, and thereby requiring a battery having a sufficient energy supplying ability.
However, it becomes difficult to supply sufficient energy to the camera for driving it by a conventional primary battery or rechargeable battery because of reduction in size and weight of the camera.
To solve the problem, small fuel cells are being watched. The fuel cell has higher power generation efficiency than a conventional power generation system, and produces clean wastes. Furthermore, an energy supplying ability of the fuel cell is several or dozens of times that of the conventional batteries. Therefore, the fuel cell is useful as a power source for a small electronic apparatus (see Japanese Laid-Open Patent Applications 2003-344919, 2003-295284 and 2000-268835, for example).
The fuel cell comprises a cell section in which a plurality of cells are laminated, a fuel tank section which reserves fuel that will be fed to the cell section, a fuel feed section which feeds the fuel in the fuel tank section to the cell section, a fuel feed path through which a hydrogen storing material is fed to the cell section, and a distributing section which gathers generated electric power to store it temporarily and outputs it usually stably.
On the other hand, a grip portion is provided in the camera, which protrudes in a camera thickness direction and has a substantially circular arc shape to make it easy to grip the camera. The shape of the grip portion is suitable for housing conventional cylindrical batteries. Arranging the heavy batteries in the grip portion makes the weight balance of the camera gripped by a user good.
However, the cell section of the conventional fuel cell has a structure in which a plurality of cells having the same size are laminated, and the exterior shape thereof is generally rectangular parallelepiped. Therefore, a comparatively large space leaves in the grip portion by arranging such a cell section therein. In other words, the space in which the fuel cell is arranged cannot be used effectively.
In addition, even a fuel cell which is small and has a large energy supplying ability requires increasing the entire output by laminating the cells as many as possible to increasing an output voltage, or by increasing the area of each cell to increase an output current, in a case where the fuel cell is used for an electronic apparatus requiring a large amount of power.
Furthermore, in a camera using a fuel cell as a power source battery, to make the camera easy to use for a user, it is required to optimize the arrangement of members that constitutes the fuel cell so that growing in size of the camera can be suppressed and a large-capacity fuel cell can be used.